Temperature and aggression: Effects on quarterly, yearly, and city rates
of violent and nonviolent crime.

Journal of Personality and Social Psychology, 52, 1161-1173.

Abstract

The hypothesized relation between uncomfortably hot temperatures and
aggressive behavior was examined in two studies of violent and nonviolent
crime. Data on rates of murder, rape, assault, robbery, burglary, larceny-theft,
and motor vehicle theft were gathered from archival sources. The first three
crimes listed are violent; the latter four are less violent (labeled nonviolent).
On the basis of previous research and theory (Anderson & Anderson, 1984),
it was predicted that violent crimes would be more prevalent in the hotter
quarters of the year and in hotter years. Furthermore, it was predicted that
this temperature-crime relation would be stronger for violent than for nonviolent
crime. Study 1 confirmed both predictions. Also, differences among cities
in violent crime were predicted to be related to the hotness of cities; this
effect was expected to be stronger for violent than for nonviolent crimes.
Study 2 confirmed both predictions, even when effects of a variety of social,
demographic, and economic variables were statistically removed. Theoretical
and practical implications are discussed.